But in the chilly coastal tundra of Chukotka, in the remote north-east of Russia, conservationists are doing exactly that. Beginning in 2012, Russian and British ornithologists have been taking the eggs from the nests of spoon-billed sandpipers. These little wading birds are critically endangered.

This is no sport, however, and it is entirely legal. The conservationists are raising the stolen chicks themselves, because that way the young birds have a far better chance of survival. Once they are large enough to survive on their own, they are released into the wild.

It is a desperate, last-ditch approach to conservation. But those involved are doing it because the spoon-billed sandpiper's situation is equally desperate.

There are only about 200 breeding pairs of spoon-billed sandpipers left in the wild. The population has declined rapidly over the last few decades.

This is a migratory journey of some 4,970 miles, undertaken by a bird no larger than a sparrow

The source of this crisis does not lie in their breeding habitats in Russia, but far to the south.

Once a young spoon-billed sandpiper has reached the right size, it embarks on an epic migration. It will head south to the Chinese and South Korean shores of the Yellow Sea, and then on to South East Asia.

This is a migratory journey of some 4,970 miles (8,000km), undertaken by a bird no larger than a sparrow. And it is on this journey that the sandpipers face their greatest challenges.

Away from the Russian tundra, spoon-billed sandpipers are shorebirds. They feed on intertidal mudflats, which are home to millions of small invertebrates.

Most of their eggs and chicks fall victim to predators

But in China and South Korea, these once vast muddy beaches have been converted to dry land for agriculture and industry. That means there are fewer places for the birds to refuel on their gruelling migration.

The habitat loss in the Yellow Sea is a crisis for many migratory shorebirds. These birds all travel along the East Asian Australasian Flyway, which stretches halfway around the world and is one of the great bird migratory routes. Bar-tailed godwits and eastern curlews are also in population free-fall.

Shorebird hunting is also a problem, particularly in South East Asia and south China. Spoon-billed sandpipers are too small to be worthwhile targets for hunters, but they are caught as bycatch in the mist nets set for larger species.

To offset these losses, the sandpipers need to produce lots of young. But that is also something they struggle with.

Most of their eggs and chicks fall victim to predators, in the form of larger birds, like skuas and gulls, and mammals like foxes and ground squirrels. On average, a breeding pair will produce three or four eggs each year, but they will only add one youngster every two years to the population flying south.

The head-starting project is located near the fishing village of Meinypil'gyno. In recent years, about a dozen spoon-billed sandpiper pairs have come to a nearby area of tundra to breed.

This place is by far the best-known breeding area for the species in Chukotka. It is also profoundly remote. Chukotka is three times the area of the United Kingdom and has almost no roads. Transport is by helicopter, caterpillar-tracked vehicles and quad bikes.

Each year, the team takes all the eggs from eight nests. If the eggs are stolen early enough in the season, the robbed parents will mate again and lay a new clutch. The team leaves those to their fate.

The first encouraging fact was that spoon-billed sandpiper chicks can feed themselves as soon as they have hatched and dried out. Within an hour, they start walking on their oversized legs in search of invertebrates to eat.

The young birds also know instinctively when to begin migrating and where to go. Somehow it is hard-wired in them – unlike young geese and cranes, which need parental guidance.

However, the team still had the problem of what to feed the young birds while they were in the aviary.

The tundra "is moving with mosquitoes," says Digby. "I've been up there and the clouds of mosquitoes have been so thick, you couldn't see 10 metres. It's tough for the aviculturists, but as a fresh live food it is fantastic for the birds, and they thrive on it."

We used the vacuum cleaner to suck mosquitoes into a bag

But during the first year of head-starting, the team faced a crisis. Their young charges would not eat the dried food, and strong winds meant there were no mosquitoes in the immediate area.

They had to go mosquito-hunting in remote valleys, away from the winds.

"There was a whole expedition organised with a quad bike, a vacuum cleaner and a portable generator," says Syroechkovskiy. "We used the vacuum cleaner to suck mosquitoes into a bag, which we then brought back to feed the chicks."

It was a bizarre thing to do, but it worked. "That way we saved our first spoon-billed sandpiper chicks," says Syroechkovskiy.

Now, the project team collects mosquitoes from these dense swarms around the clock. There is no night in the far north at this time of year, and the chicks need lots of food to be ready for their first migration.

"These chicks hatch out and they weigh only 5 grams," Digby says. "They look like little bumblebees with huge feet. By the time they are 20 days old, they are fully fledged and we then release them. At 23 to 25 days old, these birds start that incredible migration."

In 2014, the first head-started birds reappeared at Meinypil'gyno. They had survived the round trip.

Then in 2015, several returnees paired up with wild birds to breed. It is too early to say if the 2016 returnees will also breed successfully, but there is no particular reason to think that they will not.

There is also evidence of a wider gain, says Syroechkovskiy. "In the summer of 2015 we recorded a slight increase in our local population of spoon-billed sandpipers for the first time, after a very steep decline in the previous six years. When you look in detail at the data, you can see the increase is happening because of head-starting."

"Increasingly we are proving that head-starting works," says Syroechkovskiy. "It's quite a special moment when you see all your efforts delivering a result."

However, the team is clear that head-starting alone is not going to save the spoon-billed sandpiper from extinction. In fact, the species is doomed in the wild unless the urgent issues of habitat destruction and hunting can be solved.

Success in saving the spoon-billed sandpiper depends on international cooperation on the Flyway

"Head-starting is giving us a little more time for rather intensive activities for conservation of the species in the non-breeding grounds," says Syroechkovskiy. "Work on preventing hunting in Myanmar, and trying to prevent habitat loss in China, in particular, is equally very important to what we are doing on the Russian breeding grounds."

Ultimately, the only way to save this tiny bird is to preserve the East Asian Australasian Flyway. Every step of it is essential.

"Success in saving the spoon-billed sandpiper depends on international cooperation on the Flyway," says Syroechkovskiy.

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